package WordCount;
import Snowball.*;
import MailLogger.*;
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.util.Vector;
import java.util.HashSet;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextInputFormat;
import org.apache.hadoop.mapred.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * This is an example Hadoop Map/Reduce application.
 * It reads the text input files, breaks each line into words
 * and counts them. The output is a locally sorted list of words and the
 * count of how often they occurred.
 *
 * To run: bin/hadoop jar build/hadoop-examples.jar wordcount
 *            [-m <i>maps</i>] [-r <i>reduces</i>] <i>in-dir</i> <i>out-dir</i>
 */
public class WordCount extends Configured implements Tool {

  /**
   * Counts the words in each line.
   * For each line of input, break the line into words and emit them as
   * (<b>word</b>, <b>1</b>).
   */
  /**
  word.set(validTerm);
  output.collect(word, one);
  reporter.setStatus((String)validTerms.get(j));
  **/
  public static class MapClass extends MapReduceBase
    implements Mapper<LongWritable, Text, Text, Text> {

    private Text text = new Text();
    private Text text2 = new Text();
    //private final static IntWritable one = new IntWritable(1);
    private Class stemClass;
    private SnowballStemmer stemmer;
    private MailLogger l = new MailLogger("chintown@gmail.com");
    
    public void map(LongWritable key, 
                    Text value,
                    OutputCollector<Text, Text> output,
                    Reporter reporter) throws IOException {
      Pattern legalChar = Pattern.compile("[\\p{Space}\\p{Graph}]+");
      Matcher m;

      String line = value.toString();

      StringTokenizer itr = new StringTokenizer(line,"\t");
      String token = "";

      Vector<String> validTerms;
      String validTerm;
      String validAssociatedTerm;
      
      int test_times = 10;
      int count = 0;

      for (int i=0; i<2; i++) {
        token = itr.nextToken();
        if (i == 1) {
          m = legalChar.matcher(token);
          if (!m.matches()) { //the line contains some non-US-ASCII characters, skip this line!
            continue;
          }

          count += 1;
          token = token.toLowerCase();
          validTerms = this.customizedTokenizer(token,reporter);
          for (int j=0; j<validTerms.size(); j++) {
            validTerm = (String)validTerms.get(j);
            text.set(validTerm);
            for (int k=0; k<validTerms.size(); k++) {
              validAssociatedTerm = (String)validTerms.get(k);
              text2.set(validAssociatedTerm);
              //if (!validTerm.equals(validAssociatedTerm)) {
                output.collect(text, text2);
              //}
            }
          }
          break;
        }
      }
    }
    private Vector<String> customizedTokenizer(String qry, Reporter reporter) {
      Vector<String> finalValidTerms = new Vector<String>();
      HashSet<String> uniqueTerms;
      Vector<String> validTerms = new Vector<String>();
      String term;
      String validTerm;
      
      try {
        stemClass = Class.forName("Snowball.englishStemmer");
        stemmer = (SnowballStemmer) stemClass.newInstance();
      } catch (Exception e) {
      }

      StringTokenizer itr2 = new StringTokenizer(qry, " .,:;@?!<>()[]{}=+*|/\\");
      while (itr2.hasMoreTokens()) {
        term = this.lengthFilter(itr2.nextToken(),reporter);
        if (term.equals("")) {
          continue;
        }
        else if (term.indexOf("%") >= 0) {
          validTerms.addAll(symbolPercentageTokenizer(term,reporter));
        }
        else {
          if (!term.equals("")) {
            validTerms.add(term);
          }
        }
      }
      String x = "";
      uniqueTerms = new HashSet<String>();
      for (int j=0; j<validTerms.size(); j++) {
        x = validTerm = validTerms.get(j);
        validTerm = this.trimMore(validTerm,'"'+"`'~#&_-^"+" .,:;@?!<>()[]{}=+*|/\\",reporter);
        validTerm = this.lengthFilter(validTerm,reporter);
        stemmer.setCurrent(validTerm);
        stemmer.stem();
        validTerm = stemmer.getCurrent();
        validTerm = this.trimMore(validTerm,'"'+"`'~#&_-^"+" .,:;@?!<>()[]{}=+*|/\\",reporter);
        validTerm = this.lengthFilter(validTerm,reporter);
        if ( (!validTerm.equals("")) && (!uniqueTerms.contains(validTerm)) ) {
          // if (validTerm.equals("google")) {
            // reporter.setStatus(x+"=>google");
          // }
          uniqueTerms.add(validTerm);
          finalValidTerms.add(validTerm);
        }
      }
      return finalValidTerms;
    }
    private String lengthFilter(String s, Reporter reporter) {
      if ( (s.length() < 2) || (s.length() > 20) ) {
        return "";
      } else {
        return s;
      }
    }
    private Vector<String> symbolPercentageTokenizer(String s, Reporter reporter) {
      Vector<String> validTerms = new Vector<String>();
      if (s.indexOf("%") >= 0) {
        validTerms.add(s.substring(0,s.indexOf("%")+1));
        validTerms.addAll(symbolPercentageTokenizer(s.substring(s.indexOf("%")+1),reporter));
      }
      else {
        if (!s.equals("")) {
          validTerms.add(s);
        }
      }
      return validTerms;
    }
    private String trimMore(String s, String list, Reporter reporter) {
      boolean is_clean = true;
      if (s.equals("")) {
        return "";
      }
      if (list.indexOf(s.charAt(0)) >= 0) {
        s = s.substring(1);
        is_clean = false;
      }

      if (s.equals("")) {
        return "";
      }
      if (list.indexOf(s.charAt(s.length()-1)) >= 0) {
        s = s.substring(0,s.length()-1);
        is_clean = false;
      }

      //System.out.println(s);
      //System.out.println(is_clean);
      if (is_clean == false) {
        s = this.trimMore(s, list, reporter);
      }
      else {
        return s;
      }
      return s;
    }
  }

  /**
   * A reducer class that just emits the sum of the input values.
   */
  public static class Reduce extends MapReduceBase
    implements Reducer<Text, Text, Text, Text> {
    
    private Text text = new Text();
    
    public void reduce(Text key, 
                       Iterator<Text> values,
                       OutputCollector<Text, Text> output,
                       Reporter reporter) throws IOException {
      //int sum = 0;
      String associatedTerms = "";
      while (values.hasNext()) {
        associatedTerms += values.next()+",";
      }
      if (associatedTerms.length() > 1) {
        associatedTerms = associatedTerms.substring(0,associatedTerms.length()-1);
      }
      text.set(associatedTerms);
      output.collect(key, text);
    }
  }

  static int printUsage() {
    System.out.println("wordcount [-m <maps>] [-r <reduces>] <input> <output>");
    ToolRunner.printGenericCommandUsage(System.out);
    return -1;
  }

  /**
   * The main driver for word count map/reduce program.
   * Invoke this method to submit the map/reduce job.
   * @throws IOException When there is communication problems with the
   *                     job tracker.
   */
  public int run(String[] args) throws Exception {
    JobConf conf = new JobConf(getConf(), WordCount.class);
    conf.setJobName("Wordcount");

    conf.setOutputKeyClass(Text.class);
    conf.setOutputValueClass(Text.class);

    conf.setMapperClass(MapClass.class);
    conf.setCombinerClass(Reduce.class);
    conf.setReducerClass(Reduce.class);

    conf.setNumMapTasks(15);
    conf.setNumReduceTasks(1);
    
    List<String> other_args = new ArrayList<String>();
    for(int i=0; i < args.length; ++i) {
      try {
        if ("-m".equals(args[i])) {
          conf.setNumMapTasks(Integer.parseInt(args[++i]));
        } else if ("-r".equals(args[i])) {
          conf.setNumReduceTasks(Integer.parseInt(args[++i]));
        } else {
          other_args.add(args[i]);
        }
      } catch (NumberFormatException except) {
        System.out.println("ERROR: Integer expected instead of " + args[i]);
        return printUsage();
      } catch (ArrayIndexOutOfBoundsException except) {
        System.out.println("ERROR: Required parameter missing from " +
                           args[i-1]);
        return printUsage();
      }
    }
    // Make sure there are exactly 2 parameters left.
    if (other_args.size() != 2) {
      System.out.println("ERROR: Wrong number of parameters: " +
                         other_args.size() + " instead of 2.");
      return printUsage();
    }
    conf.setInputFormat(TextInputFormat.class);
    conf.setOutputFormat(TextOutputFormat.class);

    FileInputFormat.setInputPaths(conf, (String)other_args.get(0));
    FileOutputFormat.setOutputPath(conf, new Path((String)other_args.get(1)));


    //conf.set("mapred.job.tracker", "local");
    //conf.set("fs.default.name", "local");
    JobClient.runJob(conf);
    return 0;
  }


  public static void main(String[] args) throws Exception {
    int res = ToolRunner.run(new Configuration(), new WordCount(), args);
    System.exit(res);
  }
}
